1. Field of the Invention
The present invention relates to an optical information recording apparatus, an optical information recording method and an optical information recording medium which may be applied to recording apparatus of a compact disc (CD) and a digital video disk (DVD), a recording method of CD and DVD and disks for such CD and DVD, for example. The recording apparatus and the recording method of the present invention may record information such as music information, a video signal or the like on an optical disk by turning on and off a recording laser in accordance with a method standardized in the CD and DVD standardization. At the same time, by gently changing the output of the recording laser, it becomes possible to record on the same disk second information which is not standardized in the CD and DVD standardization.
Also, in the optical information recording medium according to the present invention, there may be recorded new information that may be recognized by visually confirming the disk surface, in addition to the music information and video signal standardized in the CD and DVD standardization, for example.
2. Description of the Related Art
According to the patent application (Japanese patent application No. 8-205292) filed on Jul. 16, 1996 by the same assignee, displacement amounts are obtained from the ideal edge position of the reproduced signal in response to all recorded signal patterns, and the table is formed based on such displacement amounts. By using this table and recording the recording signal while changing the edge position of the recording signal in response to the pattern of the recording signal, it is possible to eliminate the jitter. Thus, it becomes possible to record the second information such as character information, graphic information and so on, which are not contained in the CD standardization, on the signal recording portion of the compact disc (CD) in an superimposing fashion. Further, according to the patent application (Japanese patent application No. 9-67843) filed on Mar. 5, 1997 by the same assignee, an ID (identification) pattern such as a bar code or the like formed by a watermark is recorded on the lead-in or the signal recording portion of the optical disk and such recorded pattern is detected electrically, whereby a disk ID or cipher is read out to thereby prevent the illegal copy or piracy. Furthermore, according to the patent application (Japanese patent application No. 9-298328) filed on Oct. 3, 1997 by the same assignee, there is provided a circuit for transforming polar coordinates of a radius (track number) and a rotation speed (number of FG pulses) indicative of the position in the cutting process into orthogonal coordinates in real time, thereby making it possible to execute the cutting process by using data expressed by the orthogonal coordinates system as they are. Of course, these optical disk apparatus are able to record an EFM (Eight-to-Fourteen Modulation) modulated signal standardized in the compact disc standard in addition to information such as character information and graphic information. Accordingly, the disk thus recorded by the above optical disk apparatus may be reproduced by a conventional player, and also it becomes possible to manufacture a disk in which character and graphic information are recorded on the disk signal portion thereof and in which the value added is improved.
However, according to the above-mentioned conventional method, the second information such as character information, graphic information and so on is recorded as the change of the laser output. As a result, there is then the possibility that signal characteristics will be fluctuated at the boundary portion in which the laser output is changed. Therefore, the laser output could not be changed largely. As a result, there is then the problem that second information such as recorded character information, graphic information and so on is not made clear sufficiently.